The European patent EP2614198, which describes a device for storing a motor vehicle that is able to move transversely in relation to its longitudinal axis on a storage site, is known in the state of the art. This driverless device comprises a motorized frame that is parallel to the longitudinal axis of the vehicle. A pair of forks are moved horizontally to fit in on one side of the vehicle's wheels.
The German patent DE1228390 describes a device consisting of a platform supporting two transversely movable straddle arms, each extended by movable lateral arms that come into contact with the tread of each wheel. This platform is mounted on castors for moving the vehicle along a path formed in a pit. The Chinese utility model CN2399477 describes a parking device consisting of a straddle arm of constant length supporting a first fixed subframe and two movable subframes each actuated by a cylinder.
Also known is the patent application WO2005/059276, which describes a truck and a parking system using this truck to transport passenger cars and the like. The truck of the present invention comprises a main body that can be moved and blocking means having at least a first and a second movable plate and at least one pair of locking jaws. The parking system of the present invention comprises a loading table, a differential table that is movable in relation to the loading table, a truck that is movable in relation to the differential table, a longitudinal drive mechanism, a linear power tube transmission mechanism, and a motorized valve station combined with an electrical control system. The truck of the present invention has a simple structure and facilitates flexible and automatic positioning, it allows locking and lifting passenger cars or vehicle chassis of various wheelbases, and it enables bidirectional transport as well as stowage or retrieval of passenger cars. Furthermore, U.S. Patent Publication No. 2010/0086385, which describes another example of a vehicle moving device within a parking lot, is also known.
The side-loading solution such as that described in patent EP2614198 requires a large space on the side of the vehicle to be able to approach the transport device, place it parallel to the vehicle and actuate the forks that lift the vehicle. The solution described in the German patent DE1228390 implies a certain height for the assembly, formed by the platform, the longitudinal straddle arms and the castors, that does not allow for it to be introduced under modern vehicles whose ground clearance does not exceed a few centimetres.
The solution described by utility model CN2399477 requires two subframes to be moved, with two independent cylinders, each of these subframes having castors, making it very difficult to move and guide the device. Yet, the manoeuvrability of the device is essential for an application such as vehicle storage in a parking lot and it requires the ability to move with very small radii of curvature. The solution proposed by utility model CN2399477 enables rectilinear movement, or at best with a very large turning radius, making it impossible to move in restricted spaces such as a car park where one seeks to optimize space and increase vehicle density. These solutions of the prior art are therefore not suitable for driverless movement of a four-wheel vehicle in a simple, robust and reliable manner.